This project proposes to explore the determinants of individual variance in the gender-typicality of women's gender role behavior. it approaches the problem through the theoretical integration of two separate theories of gender role development: a social science model based on socialization and social experience, and a biological model based on endocrine hormone effects on behavioral predispositions. Attention is focused on reproductive and occupational behavior. The theoretical model proposes that social processes and steroid hormones acts additively, interactively, and non-recursively to affect gender role behavior in women. A sample of 200 college women will be studied. Blood samples and questionnaire data will be gathered for five years. Serum will be assayed for testosterone, sex hormone binding globulin, estradiol, progesterone, androstenedione, and luteinizing hormone. The longitudinal analysis offers the first opportunity to test the causal direction of hormone-behavior relationships and their possible non- recursiveness.